Harrisburg, Pennsylvania Weather History

Pennsylvania, United States  •  45 yrs data 📍 40.2793°N, 76.8463°W
°F / °C
☀️

Quick Climate Facts

(1981 – 2025)
Hottest Month
🔥
Jul
Avg 74.1°F
Min 53.4°F
Max 94.8°F
Coldest Month
❄️
Jan
Avg 27.7°F
Min 2.7°F
Max 52.7°F
Wettest Month
🌧️
Sep
110 mm
Driest Month
🏜️
Feb
68 mm
Most Humid
💧
Jan
87%
Least Humid
🌬️
Aug
68%
Highest Ever
🌡️
102.2°F
Jul 2010
Lowest Ever
🧊
-23.8°F
Jan 1994
Monthly Climate Data
Month 🌤️ High Low Avg Humid % Rain (mm) Wind (m/s) Solar (kWh/m²)

Showing average climate conditions across 45 years (1981–2025)

🌍 Weather in Harrisburg Across Seasons

❄️ Winter in Harrisburg

January is Harrisburg's coldest month, with average lows reaching 2.7°F.
🌡️ December to February (avg)  ·  5.9°F54.7°F

🧥 Pack heavy layers and prepare for snow — this is a Severe Winter destination.

☀️ Summer in Harrisburg

Summer temperatures in Harrisburg peak in July, climbing to 94.8°F.
🌡️ June to August (avg)  ·  50°F93°F

🌤️ Early mornings and evenings are most comfortable during this Hot Summer season.

🌧️ Rainy Season in Harrisburg

Harrisburg sees its highest rainfall in September, receiving approximately 110 mm of precipitation.
🌧️ June to September (avg)  ·  up to 110 mm

☔ Moderate Rainfall expected — carry rain gear and plan outdoor activities around these months.

📅 Monthly Averages

🌡️ Temperature Patterns

Monthly averages · 1981–2025 climate normals · °F

🌡️ Harrisburg Monthly Temperature Guide

Jul is the hottest month in Harrisburg, with average highs reaching 94.8°F, while Jan is the coldest with lows dropping to 2.7°F.

Temperatures rise steadily from spring, peak in Jul, and gradually decline through fall into winter.

These seasonal patterns make summer ideal for outdoor activities, while winters bring freezing conditions and heavy snowfall.

🌧️ Rainfall Distribution

Monthly rainfall · 1981–2025 seasonal trends · mm/month

💨 Humidity & Wind Speed

Monthly averages · 1981–2025

💧 Rainfall & Humidity in Harrisburg

Harrisburg receives its highest rainfall in Sep, while humidity peaks during winter months.
🌧️ Wettest: Sep — 110 mm ☀️ Driest: Feb — 68 mm

💧 Humidity peaks at 87% in Jan · annual avg 78%

🌍 Climate Summary

Avg Annual Temp:51.8°F
Avg Annual Rainfall:1112 mm
Avg Humidity:78%
Data Period:1981 – 2025

Harrisburg Climate Overview

Harrisburg has a temperate climate with warm summers and freezing winters.

Temperatures peak in Jul and drop to their lowest in Jan, while rainfall is highest during autumn months.

Humidity remains high throughout the year, especially during winter months, creating cold and damp conditions.

📈 Yearly Trends

The warmest year in Harrisburg's recorded history was 2024 (avg: 56.1°F), while the coldest year was 1986 (avg: 48.6°F), based on annual average temperatures.

📊 Key Climate Trends

🌡️ Annual Temperature Trend

View Range:

Average annual high/low · Last 10 years · °F

Harrisburg's temperatures shows a slight warming trend over the past decade. The highest recorded temperature reached 102.2°F in Jul 2010, while the lowest dropped to -23.8°F in Jan 1994.

🌧️ Annual Precipitation

View Range:

Total annual precipitation · Last 10 years · mm/year

Annual rainfall in Harrisburg shows noticeable variation. Rainfall has decreased in recent years compared to earlier periods.
📋 Yearly Climate Data Overview

🔥 hottest  ·  ❄️ coldest  ·  🌧️ wettest

Year Min Temp Avg Temp Max Temp Rainfall (mm) Avg Humidity Avg Wind

🏙️ Other Cities in Pennsylvania

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❓ Frequently Asked Questions

What is the hottest month in Harrisburg?
Based on 45 years of data (1981–2025), Jul is typically the hottest month in Harrisburg, Pennsylvania, with average high temperatures around 94.8°F.
What is the coldest month in Harrisburg?
Jan is the coldest month in Harrisburg, with average low temperatures around 2.7°F.
What is the rainiest month in Harrisburg?
Sep receives the most rainfall with approximately 110 mm, while Feb is the driest with 68 mm.
What was the highest temperature ever recorded in Harrisburg?
The highest recorded temperature was 102.2°F in Jul 2010. This is part of the historical record spanning 1981–2025.
What was the lowest temperature ever recorded in Harrisburg?
The lowest recorded temperature was -23.8°F in Jan 1994.
How many years of data does this page cover?
This page covers 45 years of climate data from 1981 to 2025. As new data is added to the database the page automatically reflects the updated coverage.
How much sunlight does Harrisburg get?
Harrisburg receives the most sunlight in Jun with an average solar radiation of 5.93 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning, agriculture, and understanding seasonal sunshine availability in Pennsylvania.
Where does this weather data come from?
All climate data is sourced from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite and model data. It provides monthly averages for temperature, precipitation, humidity, wind speed, and solar radiation.

📚 Data Source

All weather data is sourced from NASA POWER (Prediction of Worldwide Energy Resources), a NASA project providing solar and meteorological data for renewable energy, building efficiency, and agricultural research.

Parameters included:
  • Temperature (Min, Max)
  • Precipitation
  • Relative Humidity
  • Wind Speed
  • Solar Radiation
Data specifications:
  • Resolution: Monthly
  • Spatial: 0.5° × 0.625°
  • Source: MERRA-2
  • Coverage: 1981–2025
  • Years: 45